Heptavalent Pneumococcal Conjugate Vaccine Reduces Infection Risk

SAN DIEGO, CA—Vaccination with heptavalent pneumococcal conjugate vaccine tended to reduce the risk of putative serious pneumococcal infections with about 45% compared to unvaccinated patients, according to results from an observational cohort study, as presented at the 2013 ACR/ARHP Annual Meeting.

A total of 505 patients with rheumatoid arthritis (RA) and spondylarthropathy (SpA) including psoriatic arthritis, were immunized with a single dose of PCV7. Of these, 497 patients (RA=248, SpA=249) were included. At vaccination, RA patients were treated with methotrexate (n=84), anti-TNF + methotrexate (n=87) or anti-TNF as monotherapy (n=77). SpA patients were treated with anti-TNF as monotherapy (n=81), anti-TNF + methotrexate (n=82) or NSAIDs/analgesics (n=86).

Each vaccinated patients was matched with four reference subjects (n=1988) from the same geographic area–this cohort was considered unexposed to the conjugate pneumococcal vaccination. All events occurring 4 years before vaccination and up to 4.5 years after vaccination were divided into serious infections (eg, pneumonia, other lower respiratory infections, meningitis, sepsis, septic arthritis) and non-serious infections (eg, upper respiratory infections, otitis media and sinusitis).

Dr. Bengtsson and her team concluded that the point estimate of ratios of relative risk suggested a 45% reduced risk (non-significant) of serious infection in vaccinated patients compared to the unexposed group (0.55, 95% CI 0.25–1.22). However, time to first event of all infections pre- and post-vaccination did not differ between the groups (0.82, 95% CI 0.49–1.38). In addition, mean time to first serious infection was significantly longer for immunized patients compared to the unexposed group (48.5 months [47.9–49.0] vs. 47.0 months [46.7-47.3]), respectively.